Mu Applications Solutions

2007 Mu Alpha Theta National Convention

======

1. B - The velocity of the rock in the x-direction is = 50 and the y-direction is. At t = 2 the total magnitude of velocity is .

2. B - Average rate at which the pages are viewed is =

3. C - Volume =

4. A - ,

5. C – Base of roof has equation .

Base of triangle = 2y, height of triangle is y

Volume of roof =

6. C - ,

7. D – Total Area = 77/60

x / 0 / 1/2 / 1 / 3/2
f(x) / 1 / 2/3 / 1/2 / 2/5
Area of Rectangle / 1/2 / 1/3 / 1/4 / 1/5

8. A - ,

9. D - The particles speed is increasing when both velocity and acceleration are both positive or both negative. , . Velocity is positive and negative on . Acceleration is negative and positive when . Speed will be increasing on the intervals .

10. B - , .

,

11. C - ,. Surface Area =

Cost = Minimize cost by taking derivative and setting equal to 0: , r = 3. Cost = 162π

12. A - .

1st 64 feet; , , .

2nd 64 feet; , ,

1st – 2nd

13. B - ,

14. B- Average rate will just be slope from .

15. C - Volume =

16. D -

when ,

when ,

when

17. E - slope of tangent line is which makes an angle of 60 degrees with the horizontal.

slope of makes a slope of 30 degrees with the horizontal. The difference in the angles is 30 degrees and cos (30) is .

18. C- SA

19. C -

. speed =

20. A -

x = 0 is min, x = 40 is maximum

21. A – Area =

22. B - =

23. A -

24. A -

Maximize y = 0, 15, 25

0 and 25 yield minimums so y = 15 and x =10. 15-10 = 5

25.C- Use to approximate.

26. B - . Separate variables and integrate:

Given

Particular solution:

27. B - A= =

28. C - The center of the ellipse is (-9,5) and is 9 units from the y-axis. a = 5 and b = 4. The area of the ellipse is . Use Pappus:

29. E - f(x)=g(x) Curves intersect at 0,1,2

Area = =

30. D - r = 6

The area of the trapezoid equals the sum of the area of the 3 triangles.

A(x),=

A’(x) = , A’(x) = = 0

solve for x, x = 3.

Area of trap =